Process of smelting lead sulfid.



UNITED STATES,

PATENT orrrcn.

ANSON G. BETTS, OF TROY, NEW YORK.

PROCESS OF SMELTING LEAD S ULFID.

Specification of Letters Patent.

Patented April 3, 19 06 Application filed May 26,1906. Serial No.262,489.

' from the matte.

In my application, Serial No. 208,946, filed May 20, 1904, I described aprocess of smelting lead sulfid with sodium-carbonate, carbon and ironoxid, or manganese oxid. By using a well-proportioned furnace charge anda moderately-high heat three separate products may be obtained insteadof twonamely, lead, matte, and slag. Samples of the matte have shown byanalysis S thirty-six per cent. iron, 33.3 per cent.; lead, two percent.; sodium, twenty-nine per cent.; calcium, .4 per cent, while theslag produced at the same time showed on analysis: FeO, 7.2 per cent.;SiO thirty-nine per cent.; CaO, 13.5 per cent.; MgO, .6 per cent.; A1 023.3 per cent.; Na O, 17.7 per cent. In my application, Serial No.262,490, filed herewith, for improvements in Smelting lead sulfid, Ihave shown and claimed methods of smelting lead sulfid, producingsimilar heavy metalalkali metal mattes and slags low in iron.

By recovering the sodium of the matte from such rocesses as a compoundnot containing su fur it can be used over again as desulfurizing agent,and by recovering the iron as oxid it, too, can be used over again asdesulfurizing agent. The recovery of the iron and sodium of the matte inuseful form I most suitablycarry out by converting or bessemerizing thefluid matte by blowing a current of air through it or over it. When airis blown through the melted matte, the temperature goes up to a whiteheat, and large uantities of sulfurous acid are given off un er theoxidizing influence of the air.

Numerous chemical changes take place, and these may be alteredintentionally by changing the working temperature, speed of working, andadditions to the charge, &c.f Examples of the reactions probably takingplace are To induce the latter reaction; silica or slag should be incontact with or added to the 6 molten matte being oxidized according toany of the well-known methods. The roducts can be used for makingcaustic a kali, alkali carbonate, water-glass, &c.; but it is especiallysuitable for smelting fresh quantities of lead-sulfidcontainingmaterials. Sodium ferrite (Fe,Na,O and carbon probably react with leadsulfid in smelting, as follows:

Fe Na,O +4PbS+5C=4Pb+5OO+2FeS.Na S.

It will be noticed that if silica is present in the converting processapplied to the matte it combines with the alkali metal; but this does noharm, for the silica in the product, if it be used in smelting lead ore,becomes eliminated in the slag. 1

The liberated sulfur dioxid andsulfur trioxid may be utilized in themanufacture of sulfuric acid by well-known methods.

What I claim as new, and desire to secure by Letters Patent, is

1. The rocess of converting lead sulfid into meta lic lead and sulfurousgas which consists in reacting on it with materials containing an alkalimetal and a heavy metal other than lead, roducing metallic lead, and

a heavy metal-a1 ali-metal matte, and elimi- 9 nating a large part ofthe sulfur in combination with the alkali metal by air oxidation.

2. The rocess of converting lead sulfid into meta lic lead and sulfurousgas which consists in reacting on it with materials containing an alkalimetal and a heavy metal other than lead, producing metallic lead, and

a heavy metal-alkali-mbtal matte, and eliminating a large part of thesulfur from the fused matte by air oxidation.

3. The rocess of converting lead sulfid into meta lic lead and sulfurousgas which consists in reacting on it with materials containingan alkalimetal and a heavy metal other than lead, reducing metallic lead, and aheavy metal-a kali-metal matte, and eliminating sulfur from the fusedmatte with an air-blast.

4. The recess of converting lead sulfid into meta lie lead and sulfurousgas which consists in reacting on it with materials containing an alkalimetal and a heavy metal other than lead, producing metallic lead, and

a heavy metal-alkali-metal matte, and eliminating sulfur from the fusedmatte by blowing a current of air through it when melted. 5. The rocessof converting lead sulfid into meta lic lead and sulfurous gas whichconsists in reacting on it with materials containing an alkali metal andiron, producing metallic lead and an iron-alkali-metal matte,

separating the lead and some slag from the matte, and oxidizing thefused matte by blowing a current through it when melted.

6. The process of converting lead sulfid into metallic lead andsulfurous gas which consists in reacting on it with materials containingiron and sodium, producing metallic lead and an-iron-sodium matte,separating the lead, and blowing a current of air through the meltedmatte.

7. The process of smelting lead ore which consists in reacting on itwith materials containing iron and sodium, producing metallic lead andan iron-sodium matte, separating the lead, blowing a current of airthrough the melted matte, and using the product in smelting leadore. 1

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ANSON G. BETTS.

Witnesses MARY BATES PAnKs, W. B. BARNHISEL.

